Need some info on lack of intestinal adaptation with DS

I do pre-op psych evals part-time, and therefore need to be fairly well informed about all of the various surgeries (although the surgery group I work for does not do bands (thank goodness).  I personally had RNY six years ago. One thing that I have not yet seen in any of the literature I have looked at is an explanation of why the intestinal adaptation that happens with the RNY does not happen with the DS (so the caloric malabsorption of the RNY is largely lost after 18-24 months but is more permanent for the DS).

Why the difference?  Is any  of the caloric malabsorption regained with the DS?  Any info (or links) is appreciated.

Lora

Some is regained but they by pass so much, normally, that we keep on malabsorbing. Not to the same extent as years 1 - 4 post-op but still quite a bit. A great place to research more on the DS is www.dsfacts.com.

--gina

I asked this question of a nurse at the surgeons office and she said they bypass alot more intestine than with the rny.

It's a matter of degree. The average human small intestine is 6-7 meters long. In the proximal RNY, which is pretty much all that's done any more, they bypass 1-1.5 meters. In the DS, they bypass more like 6 meters. (My surgical notes say my small intestine measured 690 cms, my common channel is only 90 cms.

In the RNY, the villi in the small intestine grow more dense, and eventually overcome the malabsorptive part of the surgery, usually in 18-24 months, leaving only restriction as a reduced intake tool.

In the DS, the length of the common channel determines the level of malabsorption.  Shorter means more, longer means less. The division of the small intestine, as described below, gives DSer's permanent malabsorption, as the rerouting of the small intestine is too great for the regrowth of villi to overcome.  That is why massive vitamin and sometimes protein supplements are necessary for DSer's for life post-op.

The division is tailored to the individual by the surgeon, using the Hess Method (named ofr Ds Surgeon Dr. Douglass Hess) to measure lengths for the biliopancratic limb,  the ailimentary limb which meet at the common channel. which typically ranges from 75 cm to 150 cm.  (Some surgeons use one length for everyone, but most use the Hess Method).

The only place with the DS where biliopancreatic juices mix with the food is in the common channel, and that is why fewer nutrients, kilocalories and fats are absorbed into the system.  That's the short explanation.

All that said, I have read that some do regain with the DS, but the rate of regain is far lower than with the RNY.. 

IMHO, there has to be some pretty wrong eating going on to regain with the DS. 

Thanks!  That helps a lot.  Good explanation.

Lora

Thanks to all.  I figured it had to do with the amount bypassed, but was not sure if it also had to do with what area is bypassed, etc.  I do occasionally have someone come in who has not made a firm decision on what surgery to have, so I want to be able to help them talk through the various aspects of the surgeroes they are considering. (I never advise them on what surgery they should have (even when they want a band, I keep my mouth shut and just ask if they have looked at the long term statistics on it), but I do want to be able to listen to their thought processes and point out incongruities between what they say they want, or think is important, and what they will be getting with the surgery/surgeries they are considering.

Lora

Actrually, some of the malabsorption has to do with which areas are bypassed.   According to my classes, there are different portions of the small intestine where nutritional components are absorbed.  After the resection, the area that absorbs fats (lipids) is almost non-existent...that's one reason DSer's malabsorb 80% of all dietary fats.  The other is that the biliopancratic enzymes do not have a long enoughtime in contact with the food (chyme) in order to break down the fats, so it just simply passes through as waste.

This is what I read in some medical literature regarding the DS.  I'll try to find it for you. 

Lora,

It is not that it does not happen like the RNY; it does happen.  But, not to the degree that it occurs in the RNY and it usually happens much further out.  As with all of us, the mileage varies, but I noticed a slight difference around 5 years, then a big difference between years 9 and 10 in my absorption rate.  

Here is a study discussing outcomes at 3 years out:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856567/

Hope this helps.

Best wishes,

Sharon

Everyone has explained this very well, but I just wanted to correct one detail from above - the amount of small intestine bypasssed with proximal RNY is generally much less than even the 1 1.5 meters our wonderful Ms. Batt stated. RNY does bypass the entire duodenum, but this is just a short (though very important) portion of the small intestine. It then bypasses just a very small amount of the jejunum.

The DS bypasses most, but not all, of the duodenum, so as to preserve the pyloric valve, but goes on to bypass far more of the rest of the small intestine. Different surgeons bypass different amounts of small intestine, some use a standard measurement for everyone, typically leaving 100 to 150 cm common channel, others do what is called the Hess method to deetermine the lengths of the different channels, but either way, the entire jejunum and some of the ileum are bypassed. So while our small intestine does adapt, we start out with so much less small intestine in play that we continue to malabsorb calories for life, while RNY malabsorption of calories is much less to start with and drops to to close to nothing pretty fast.

I also wanted to commend you for how you handle patients' surgery choices. we hear stories of psych evaluators directing patients to or from different surgical options, often based on limited or incorrect knowledge about the different options. It's very impressive that you don't do this. Thank you.

Larra